The SR-303 came out 20 years ago and was the mid-range Lambda model at the time, sitting between the SR-202 and SR-404. It (supposedly) uses the same drivers as the SR-404, but the cable is different, with lower capacitance on the SR-404.
The design hasn’t changed much in the Lambda line between the first model (SR-Lambda in 1979) and the current L300/L500/L700. The SR-303 has a beige plastic frame, that does not feel premium but it’s at least comfortable (provided you can get a good fit) and quite light.
○ Release : 1999
○ Current status : Discontinued
○ Type : Over-ear / Open-back
○ Measured weight : 332g
○ Impedance : 145k Ohms
○ Sensitivity : 100dB/100V
○ Average used price : $200-250
I do not have a huge experience with Lambda headphones, and only heard the SR-407, Lambda Pro and SR-L700 previously. I also heard an SR-303 during a meet, but the experience was very short. The SR-303 is an unremarkable sounding headphone to me.
The bass has good extension since I usually dont have issues getting a good seal with Lambdas. It extends all the way down to 20 Hz, while modern Lambdas have ported pads, leaking and resulting in bass roll-off below 60 Hz. The bass quality is good, but like most estats, the impact is light and it doesn’t really hit in any hard way.
The midrange might be the best I’ve heard in a Lambda. The SR-407 was a bit more agressive, while the SR-L700 has a big 1 khz bump and more recessed upper-mids. The Lambda Pro sounded withdrawn. This SR-303 has a moderate 1.5khz shout but doesn’t sound too offensive during listening.
The treble is pretty good – barely elevated around 9-10 kHz, with tolerable amount of air (unlike the older Lambdas which can have absurd amounts of upper-treble). The whole tonality is honestly decent. The upper-midrange is the only weird area, as usual with Stax headphones.
The presentation is slightly lean, but the treble isn’t too elevated and the bass extends well so it’s not as lean as a Lambda Pro. The midrange sounds a bit thin and artificial. Generally the overall timbre of the SR-303 is far from natural, and other electrostatic models are much better in that regard (Koss ESP-950, Stax SR-007, Sennheiser HE-60).
Nothing really impressive about the stage and technicalities. For ~$200-250 used, it’s very fast and pretty detailed, but lacks macrodynamics to a big degree. An HD600 is punchier in the midrange, but the SR-303 has the better sub-bass.
The more I listen to headphones, the more I realize I value dynamics and overall punch/impact more, so I kinda stay away from electrostatics, as they don’t satisfy me and are too smooth and “light” sounding (with very few exceptions). The SR-303 is arguably a decent sounding headphone for the price, and a good entry in the estat world, but simply not my cup of tea.
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